I purchased an '08 ZZR600 with 5,600 miles on it about a month ago, and couldn't be happier with it. It is by far the best all-around motorcycle I've ever ridden.
Even though it is based on older technology (the carburated '00-02 ZX-6R), it gives up nothing in the way of handling to more modern 600 supersports, and is only a tick or two slower.
The riding position (mine has Helibar risers) and seat are VERY comfortable for a sport bike, and there is plenty of leg room as well (I have a 32" inseam).
Decent amount of low-end power for a 600, so it's fun around town as well as at higher speeds. The passenger seat is pretty generous, making it a good 2-up bike.
I'm averaging 45 mpg. with moderate riding, so no complaints there. However, like a lot of supersport bikes, it does require premium fuel. Sadly, '08 was the last year Kawasaki made this bike.
Bottom line: If you want the last of the comfortable, supersport street bikes, find yourself a ZZR.
Upgrades/Accessories: Helibar handlebar risers and Yoshimura slip-on exhaust.
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